Rotary well drilling rigs



United States Patent ROTARY WELL DRILLING RIGS Odie Colquitt, Denver,Colo., assignor to The Winter- Weiss Co., Denver, (3010., a corporationof Colorado Application February 17, 1955, Serial No. 488,909

4 Claims. (Cl. 255-23) This invention relates ot a rotary drill drivingmechanism fora rotary well drilling rig, and while more particularlyadaptable for use on a portable rotary rock drilling rig such asdescribed and illustrated in applicants co-pending application SerialNo. 487,086 it will be found valuable for any'type of rotarywelldrilling rig.

The principal object of theinvention is to provide a relatively simple,highly efficient, lightweight rotary table structure for well drillingrigs which will maintain the drill in an accurate centered position inthe table, which will operate with a minimum of power loss, and whichwill prevent the entrance of mud and sand to the'wearing parts.

Another object of the invention is to provide a rotary table structurewhich will act to automatically lock a drill stem bushing, hereinreferred to as a kelly bushing, in the table structure during thedrilling operation, and to automatically release the kelly bushing fromtheztable when the drill string is withdrawn from the well'toallow freepassage of a drill-stem-saver-substitute or kelly sub" for servicing thedrill string.

Other objects and advantages reside in the detail construction of theinvention, which is designed for simplicity, economy, and efficiency.These will become more apparent from the following description.

In the following detailed description of the invention, reference ishad. to the accompanying drawing which forms a part hereof. Likenumerals refer to like parts in all views of the drawing and throughout.the description.

In the drawing:

Fig. 1 is a vertical section'through the improved rotary table,illustrating a drill stem or kellybar in place therein in the drillingposition;

Fig. 2 is a horizontal cross-section, looking upwardly on the line 2-2,Fig. 1; and

Fig. 3 is a similar cross-sectiom looking downwardly I on the line 3--3,Fig. 1.

The improved rotary table mechanism is designed to be mounted on anydesired supporting base structure, such as indicated on the drawing at10, and comprisesan outer barrel 11 designed to be seated on and securedto the supporting base in any desired manner. The barrel 11 is closed atits top by means of an annular top ring 12 which is seated on the barrel11 and secured thereto in any desired manner, such as by means ofattachment bolts 14 extending through peripheral flanges 13.

A lower thrust bearin 'ace 15 ,is seated in the barrel 11 adjacent thebottom thereof upon a suitable bearing shoulder 16. An upper thrustbearingrace I7 is inset into the top ring 12. The bearing races 15 and;'17 support suitable anti-friction bearings 18'. preferably of,the'conical roller type. The roller bearings 18 ride against and aroundinner bearing ra'ces'19 which surround a tubular gear sleeve extendingvertically through the barrel 11. The gear sleeve 20 is formed with asurrounding annular flange 21 which rests upon the lower inner bearingrace 19 to support the sleeve 20 in the barrel 11. The upper ice . 2inner bearing race 19 is supported from the flange 21 upon a tubularspacer 22 surrounding the gear sleeve 20.

An annular cap member 23 is secured on the upper extremity of the gearsleeve 20 by means of suitable countersunk cap screws, such as indicatedat 24. The cap member 23 extends outwardly over the top ring 12 andterminates at its periphery in a circular, downwardly extending dripflange 25. The drip flange 25 surrounds the upper extremity of the capring 12 and acts to prevent mud and sand from entering between the topring 12 and the cap member 23. The gear sleeve 20 is rotated about avertical axis in the barrel 11 through the medium of a ring gear 28which is secured to the upper surface of the flange 21 in any desiredmanner, such as bymeans of suitable rivets 29. A drive pinion 30 mesheswith and rotates the ring gear 28 and through it the gear sleeve 20. Thedrive pinion is fixedly mounted on the inner extremity of a pinion shaft31.

The pinion shaft 31 is supported, adjacent the pinion 30, in two opposedconventional anti-friction thrust bearings 32 which are mounted in abearing sleeve 33 mounted in the side of the barrel 11. The outerextremity of the shaft 31 is supported in a bearing collar 34 which issecured through a flange formed on the bearing sleeve 33 and to thebarrel 11 by means of suitable cap screws 35.

Thev bearing collar 34 supports the outer extremity of the pinion shaft31 in suitable ball bearings 36. The ball bearings surround a hub 37formed on a universal joint coupling 38'which is locked on the shaftextremity and through which power is ,suppliedto the shaft in anysuitable manner from any suitable source.

Inuse, the barrel 11 is maintained partially filled with lubricating oilthrough an oil nipplenormally closed by means of an oil plug 40. An oilseal is provided atthe 'top of the barrel by means of two annularhorizontal packing rings 26 embedded in the .top ring 12 andfrictionally engaging the lower surface ,of the cap member 23. An oilseal is provided at the bot om of the barrel by means of a lower annularsealing ring 27 fixed in the bottom of the barrel 11 in frictionalengagement with the lower extremity of the ,gear. sleeve 20. A packinggasket 39 prevents leakage of lubricating oilfrom the barrel 11 aboutt pn n ha '31.

The gear sleeve 20 isprovided with an axial passage for a drill stem orkelly bar 41. This passage mayhave any non-circularcross-section,preferably ahexagonal cross-section as illustrated. .The.passage is sufficiently 1 large to allow the passage of. a conventionaldrill-stemsaver-substitute, such as known in the art as a "fkelly suband indicated at 48 on the drawing. The difference in size between thekelly bar 41 and the passage in the gear sleeve 20 is accommodated bymeans of a hexagonal kelly bushing 42 having an outer contour tocorrespond to and fit snugly within the gear sleeve 20. The kellybushing 42 is supported in the sleeve 20 by means of an upper peripheralprojecting flange 50 which rests upon the .cap member 23. i

The kelly bar 41 may have any desired contour, such as square,hexagonal, or fluted. As illustrated, it is cylindrical and providedwith longitudinalridgesor keys 43,, and the kelly bushingis-providedwith keyways for slidably receiving the keys 43. Thus, torquewill be transmitted from the gear sleeve 20 throughthe kelly bushing 42to the keys .43.so as to impart drilling rota- ;tion to the kelly bar41.

. Upward movement of thekelly bushing 42 in the sleeve v:20 duringdrilling operationsnis prevented by means of two key balls 44 positionedin radially extending ball passages 45 formed at opposite sides of andextending completely through the wall of the kelly bushing 42. vThediameters of the balls 44 exceed the thickness of the aasaaqs I wall ofthe kelly bushing 42 so that, when in contact with the kelly bar 41,they protrude from the kelly bushing into ball sockets 46 formed in thesleeve 20. Therefore, it will be seen that when the kelly bar'41 is inthe operating or drilling position, it will be impossible for the kellybushing 42 to move upwardly in the sleeve 20. The kelly bar 41, however,is provided with a plurality of oppositely positioned ball pockets 47positioned a. distance above the lower extremity of the kelly bar equalto the distance the balls 44 are spaced above the bottom of the kellybushing 42. Thus, when the kelly bar is elevated until its lowerextremity aligns with the bottom of the kelly bushing 42, the pockets 47will align with the balls 44, allowing them to move inwardlysufficiently to release them from the ball sockets 46 so as to allow thekelly bushing to move upwardly with the kelly bar.

During the drilling operation a length of drill pipe is threaded intothe lower extremity of the kelly sub 48..

When the drilling has progressed. the length of the kelly supportingsaid sleeve concentrically about said kelly bar;'means for rotating saidsleeve; a hexagonal kelly bushing fitted into the hexagonal passage insaid sleeve about said kelly bar, the hexagonal interconnectionpreventing relative rotation between said sleeve and said kelly bushing;longitudinally extending keys formed on said kelly bar and engagingkeyways in said kelly bushing so as to prevent relative rotation betweensaid kelly bushing and said kelly bar; a radial ball passage extendingcompletely through the wall of said kelly bushing;

a freely movable ball positioned in said ball passage in contact withsaid kelly bar and having a diameter exceeding the thickness of the wallof said kelly bushing so that when in contact with said kelly bar theball will bar, the latter is drawn upwardly through the gear sleeve.

1 contact,'the ball pockets 47 will be positioned horizontally oppositethe balls 44 to provide space for the latter to move radially inward.The upward movement of the kelly bushing brings the balls into contactwith the upper edges of the ball sockets 46 and this contact will forcethe balls radially inward into the ball pockets 47 to release the kellybushing and allow it to move upwardly through the gear sleeve 20 sothatthe topmost length of drillpipe may be drawn through the drill sleeve soas to project above the latter. The upwardly projectingdrill pipe is'nowlocked in the gear sleeve by means of conventional split wedge slips, asis usual in rotary drilling operationsfso as to suspend the drill stringin the well from the drill sleeve 20. The kelly sub 48 is now unscrewedfrom the uppermost length of drill pipe and a new length of drill pipeis coupled between the kelly sub and the former uppermost length. Thekelly bar is i then lifted to release the wedge slips and the kelly baris lowered to'the drilling position. The kelly bushing 42 movesdownwardly with the kelly bar and enters the passage in the gear sleeveuntil stopped by the flange 45 50. The kelly bar continues downwardly,causing the ball pockets 47 to travel away from the balls 44 to forcethe latter outwardly into the sockets 46 to automatically lock the kellybushing in place, and the drilling is re' sumed.

It will be noted that the kelly bushing requires no attention. It willlock itself in place automatically when the drill string is ready fordrilling, and will similarly automatically unlock itself as the lengthsof drill' pipe are withdrawn. i y

When the kelly bushing 42 is elevated above the gear sleeve 20 itsweight is supported by the kelly sub 48 so that there is no tendency toforce the balls outwardly from their passages 45. In use the kelly bar41, the kelly bushing 42 and the gear sleeve are protected by a coatingof hard oil'or grease; The latter maintains the balls in their passagesagainst dislodgement by vibration.

While a specific form of the improvement has been described andillustrated herein, it is desired tov be underproject partially radiallyoutward from said kelly bushing;a ball socket formed in said gear sleevepositioned to receive the outwardly projecting portion of said ball 7 sothat said ball will enter said socket and prevent withdrawal of saidkelly bushing from said sleeve; and a ball pocket formed in said kellybar and adapted to be brought into alignment with said ball when desiredto provide space which will allow said ball to move radially inward inits passage and from said socket so as to free the kelly bushing fromthe sleeve.

2. Means for rotating a kelly bar in a rotary drilling mechanism asdescribed in claim 1 having a kelly sub mounted on the lower extremityof said kelly bar of larger diameter than said bar, said ball pocketbeing positioned a distance above said lower kelly sub corresponding tothe distance from the ball to the lower extremity of the kelly bushingso that when said sub contacts said bushing said ball pocket will alignhorizontally with said ball to allow the latter to move radially inwardfrom said socket.

3. Means for rotating a kelly barin a rotary drilling mechanism asdescribed in claim 2 having a flange projecting about the upperextremity of said kelly bushing and over said gear sleeve so as to limitthe dowward movement of said kelly bushing in said gear sleeve.

4. Means for rotating a kelly bar in a rotary drilling mechanismcomprising: a vertical, tubular gear sleeve having a flat-sided axialpassage; means for rotatably supporting said sleeve; means for rotatingsaid sleeve; a fiat-sided kelly bushing adapted to axially receive said.kelly bar, said kelly bushing being slidably fitted into the flat-sidedaxial passage of said sleeve, the flat-sided shape of the bushingpreventing relative rotation between said sleeve and said kelly bushing;longitudinally extend- 0 ing. keys formed on said kelly bar and engagingkeyways in said kelly bushing to prevent relative rotation between saidkelly bushing and kelly bar; means on said kelly bushing for limitingits downward movement in said gear sleeve; ball passages formed in andcompletely through the wall of said kelly bushing at opposite sides 1 ofsaid kelly bar; a ball contained in each ball passage,

stood that the same may be varied, within the scope of the appendedclaims, without departing from the spirit of the invention. v

Having thus described the invention, what is claimed and desired securedby Letters. Patent is:

1. Means for rotating a kellybar ina rotary drilling o mechanismcomprising: a vertical, tubular gear sleeve having a hexagonal axialpassage; means for rotatably each ball having a larger diameter than thethickness of the wall of said kelly bushing so that the balls willproject oppositely outward from said kelly bushing when in contact withthe normal surface of said kelly bar; and ball sockets in said sleevepositioned to receive the outwardly projecting portions of said balls.

References Cited in the file ofthis patent I UNITED STATES PATENTS2,030,318

